I am working on a community college certification in programming and have a choice of specialization in Java ,Visual Basic ,or Visual C++. I am curious to know what specialization would be best for the current job market and increase my earning potential? Any feedback would be greatly... (5 Replies)
Hi,
I'm confused about the GCC & Linking process could somebody please briefly explain?
I have GCC 3.4.6 installed from SunFreeware. Reading the narrative alongside the package states "It was compiled to use the SUN assembler and loader usually in /usr/ccs/bin if the SUNW developer packages... (1 Reply)
Hi,
I do not use the default linker, and instead us another one and pass this argument -Wl,--dynamic-linker=<path to linker> to gcc when compiling. However, what happens if the linker is not under /lib and /lib64 and I am not able to create a symlink to the linker in /lib or /lib64 due to no... (2 Replies)
Hi all,
I would like to compile a program and get current errors and warnings report to me as « gcc -Wall ».
Does someone can give me these options to get an equivalent ?
Or the ommon option used to put them in a CFLAGS in a Makefile.
Something like :
xlc -O2 -Wall my_prog.c -o... (5 Replies)
Hai,
I have two (Pgm1.c and Pgm2.c) simple programs, which is compiled using gcc. Now we have two exe's (Pgm1 and Pgm2). When i executed the nm Pgm1 and nm Pgm2, in the listed symbols the address of main is same for both programs (08048344 T main) at run time also.
Doubt:
1) What is this... (3 Replies)
I have a build where I wish to link against and load a specific version of a library and a different version of the same library is installed on the system. I'm using a -L option to point to the version that I wish to link against but gcc still seems to choose the installed version. Is there a way... (4 Replies)
Dear Linux users,
I'm a noob at openmp, gcc and c programming. I can run my own openmp code in terminal with no problem, eg. gcc -fopenmp program.c -o program.
But now I'm trying to compile and run another person's code, it contains a makefile and multiple .c and .h files. I don't know how to... (2 Replies)
I need a lot of help with c programming.
I have the source code.
Running configure, I got one error message about a missing library.
I downloaded and successfully compiled it in another dir.
Do I throw all the new files into my source dir and run configure again ?
Thanks. (3 Replies)
Discussion started by: drew77
3 Replies
LEARN ABOUT NETBSD
__builtin_constant_p
__BUILTIN_CONSTANT_P(3) BSD Library Functions Manual __BUILTIN_CONSTANT_P(3)NAME
__builtin_constant_p -- GNU extension to determine compile time constants
SYNOPSIS
int
__builtin_constant_p(value);
DESCRIPTION
The __builtin_constant_p() is a GNU extension for determining whether a value is known to be constant at compile time. The function is
closely related to the concept of ``constant folding'' used by modern optimizing compilers.
If the value is known to be a compile-time constant, a value 1 is returned. If __builtin_constant_p() returns 0, the value is not a compile-
time constant in the sense that gcc(1) was unable to determine whether the value is constant or not.
EXAMPLES
A typical example of the use of __builtin_constant_p() involves a situation where it may be desirable to fold the computation if it involves
a constant, but a function call is needed otherwise. For instance, bswap16(3) is defined in NetBSD as:
#define bswap16(x)
(__builtin_constant_p((x)) ?
__byte_swap_u16_constant(x) : __BYTE_SWAP_U16_VARIABLE(x))
SEE ALSO gcc(1), __builtin_object_size(3), __builtin_return_address(3)CAVEATS
This is a non-standard, compiler-specific extension.
BSD December 19, 2010 BSD